To reproduce:
doc.Pages[0].CropBox = new Rect(150, 150, doc.Pages[0].Size.Width - 30, doc.Pages[0].Size.Height - 30);
Hi,
This feature is not supported in PDFViewer. To achieve this the user should use PDF Processing in order to load this document and edit it. For example to set CropBox.
Regards,
Dimitar
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